Methods are known for preparing carbonyl compounds by direct oxidation of compounds containing an activated methylene group, such as for example the esters of malonic acid, by using, as oxidants, tri- and tetravalent oxides of nitrogen, bromine or selenium dioxide.
Such methods, however, besides requiring the use of toxic and dangerous oxidants, are not catalytic and provide only low yields, wherefore they are expensive and furthermore little reproducible and generalizable, so that they are difficult to be industrially produced, particularly for large-scale productions.